X-ray technology has been used to improve the quality of medical and dental diagnosis and care; however, there are known dangers in the exposure of humans and animals to ionizing radiation such as is used in X-ray imaging. A large number of independently operated facilities, such as dental offices, use X-ray technology in routine diagnosis and treatment of medical conditions and in delivering dental care to patients. The use of an X-ray device to identify areas of tooth decay, abscess, and other pathology results in a substantial portion of the population being routinely exposed to ionizing radiation, in addition to that which naturally occurs in the ambient background.
The amount of X-ray exposure or dose delivered to patient tissue during an X-ray examination varies widely with the type of images being obtained, the age and specific model of the equipment being used, and both the skill and judgment of the practitioner. Further, an X-ray device may operate such that the expected dose is not properly calibrated, or other aspects of the device such as the quality of beam collimation or beam energy may deviate from acceptable limits. Generally there are regulations, which vary in detail from state-to-state in the United States, and from country to country, as to the frequency and methods of testing of such devices. The equipment needed for such testing is generally quite sophisticated and specialized and operated by a person specifically trained in the use thereof. As such, the frequency with which each of the facilities in a jurisdiction is tested tends to be low, often with a period of years separating successive tests.
Where X-ray film is used to record the X-ray image, the image quality also depends on the image developing technique used at the facility, the quality and freshness of the chemical solution used, and the training and work habits of the personnel. Image quality may be characterized by the sharpness and contrast of the images, and inadequate imaging quality may result in misdiagnosis or the need to take additional images, thus increasing the overall patient radiation dose.